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      <title>数据库与es怎么同步 - 交互式测验</title>
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    </head>
    <body>
      <div class="main-wrapper">
          <div class="quiz-container">
            <div class="quiz-header">
              <h1>数据库与es怎么同步 - 交互式测验</h1>
              <p>检验你对文档内容的理解程度</p>
            </div>
            <div id="quiz-content">
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      </div>

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        const quizData = [
  {
    "question": "根据文档，与其它方案相比，“定时批量同步”方法最主要的缺点是什么？",
    "options": [
      "实现过程非常复杂，需要引入Kafka等中间件。",
      "对应用代码的侵入性强，增加了业务逻辑的复杂性。",
      "数据更新存在延迟，不适合数据更新频繁的场景。",
      "性能较差，无法处理大批量数据的同步。"
    ],
    "correctAnswerIndex": 2,
    "explanation": "文档中明确指出，定时批量同步的缺点是“数据更新延迟，可能导致ES中的数据与数据库不同步”，尤其是在高更新频率的场景下。而实现复杂是CDC的特点，侵入性强是应用层同步的特点，性能良好反而是其优点之一。",
    "source": "文档中「1. 定时批量同步」部分",
    "hint": "思考一下“定时”这个词对数据新鲜度会产生怎样的影响。"
  },
  {
    "question": "文档中提到的“实时同步 (CDC)”方法，通常需要借助哪些技术来实现其复杂的数据捕获和传输流程？",
    "options": [
      "通过cron作业定期查询数据库的变更。",
      "在应用层代码中直接实现对数据库和ES的双写操作。",
      "使用Kafka、Debezium等中间件来捕泛和传输变更事件。",
      "利用简单的JDBC插件直接连接并同步数据。"
    ],
    "correctAnswerIndex": 2,
    "explanation": "文档在描述CDC的缺点时提到，“实现复杂，通常需要使用Kafka、Debezium等中间件来捕获和传输变更事件”，这揭示了其典型的技术栈，用以实现对数据库变更日志的监听和事件流处理。",
    "source": "文档中「2. 实时同步（Change Data Capture, CDC）」部分",
    "hint": "这种方法的核心是“捕获变更”，想想需要什么组件来可靠地处理这些“变更事件流”。"
  },
  {
    "question": "“应用层同步”方法虽然实时性强、灵活性高，但它最大的挑战和风险是什么？",
    "options": [
      "同步延迟非常高，无法满足实时性要求。",
      "数据一致性依赖于应用的实现，若出现故障可能导致数据不一致。",
      "灵活性差，无法根据业务逻辑定制同步行为。",
      "实现起来最简单，但功能受限。"
    ],
    "correctAnswerIndex": 1,
    "explanation": "该方法将同步逻辑与业务代码耦合，其核心缺点是“数据一致性依赖于应用的实现，如果出现故障，可能导致数据不一致”。这意味着开发者必须自行处理复杂的失败、重试和补偿逻辑，否则风险很高。",
    "source": "文档中「3. 应用层同步」部分",
    "hint": "当应用程序需要同时保证对两个不同系统的写入都成功时，如果其中一个写入失败了会发生什么？"
  },
  {
    "question": "假设一个业务场景（如电商库存系统）对数据搜索的实时性要求极高，几乎不允许延迟。根据文档，哪种同步策略最适合这个场景？",
    "options": [
      "定时批量同步，因为它实现简单，可以快速上线。",
      "实时同步 (CDC)，因为它能实时反映数据库变更，专门为需要实时搜索和分析的场景设计。",
      "第三方工具，因为它能减少开发工作量，而且所有工具都支持强实时性。",
      "数据转换与预处理，因为它能优化数据结构。"
    ],
    "correctAnswerIndex": 1,
    "explanation": "文档描述实时同步 (CDC) 的优点是“数据一致性更好，能够实时反映数据库的变更”并且“适合需要实时搜索和分析的场景”。对于实时性要求极高的场景，CDC是比定时批量同步更优越的选择。",
    "source": "文档中「2. 实时同步（Change Data Capture, CDC）」部分",
    "hint": "哪个方案的名称里就包含了“实时”并且是为“捕获数据变更”而设计的？"
  },
  {
    "question": "在数据库与ES同步过程中，实施“数据转换与预处理”步骤的主要目的是什么？",
    "options": [
      "保证数据库与ES之间的数据强一致性。",
      "提升数据同步的速度，最大化减少延迟。",
      "降低同步过程的实现复杂性和维护成本。",
      "优化数据结构，使其更适合搜索需求，并可以进行数据清洗和过滤。"
    ],
    "correctAnswerIndex": 3,
    "explanation": "文档中明确指出了数据转换与预处理的优点：“可以在同步时优化数据结构，更适合搜索的需求”以及“提供数据清洗、过滤的能力”。它通常会增加复杂性，而不是降低。",
    "source": "文档中「5. 数据转换与预处理」部分",
    "hint": "数据库的原始表结构不一定直接适用于全文检索，想想要做什么来让它变得更“好搜”。"
  },
  {
    "question": "根据文档，对于希望快速实现同步功能且不想投入大量开发资源的团队，使用Logstash等第三方工具的一个主要优势是什么？",
    "options": [
      "可以快速集成，显著减少自定义开发的编码工作量。",
      "能够支持所有数据库的全部高级特性，兼容性最好。",
      "完全不需要后续的版本更新和维护工作。",
      "提供比任何其他方案都更高的数据实时性。"
    ],
    "correctAnswerIndex": 0,
    "explanation": "文档中列出的第三方工具的优点之一是“可以快速集成，减少开发工作量”。这正是其吸引力的关键所在。同时文档也提醒，使用第三方工具可能面临兼容性问题和版本维护的挑战。",
    "source": "文档中「4. 第三方工具和框架」部分",
    "hint": "当你不想从头开始编写所有代码时，通常会选择利用现成的解决方案，这带来了什么好处？"
  },
  {
    "question": "在设计数据库到ES的同步方案时，文档强调了需要权衡“强一致性”与“最终一致性”。这属于哪个核心的设计考虑范畴？",
    "options": [
      "性能 (Performance)",
      "容错性 (Fault tolerance)",
      "一致性 (Consistency)",
      "可维护性 (Maintainability)"
    ],
    "correctAnswerIndex": 2,
    "explanation": "文档在“设计考虑”章节中明确将“一致性”列为首要考虑点，并具体说明为“需要权衡强一致性与最终一致性，选择合适的同步策略”。",
    "source": "文档中「6. 设计考虑」部分",
    "hint": "这个概念是分布式系统中的一个经典权衡点，关乎数据在不同副本或系统之间是否总是保持同步。"
  }
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        }

        function reviewQuiz() {
            const reportEl = document.querySelector('.final-score-container');
            if (reportEl) {
                reportEl.remove();
            }

            document.querySelector('.quiz-body').style.display = 'block';
            document.getElementById('quiz-footer').style.display = 'flex';
            
            currentQuestionIndex = 0;
            loadQuestion();
            updateNavigationButtons(); // Ensure nav buttons are correctly displayed
        }

        // Event Delegation for options
        optionsListEl.addEventListener('click', (event) => {
            if (event.target && event.target.matches('li.option-item')) {
                // Check if the question has already been answered
                if (userAnswers[currentQuestionIndex] === null) {
                    const selectedIndex = parseInt(event.target.dataset.index, 10);
                    selectOption(selectedIndex);
                }
            }
        });

        prevBtn.addEventListener('click', goToPreviousQuestion);
        nextBtn.addEventListener('click', goToNextQuestion);
        hintBtn.addEventListener('click', showHint);
        
        // 初始加载
        loadQuestion();
      </script>
    </body>
    </html>
  